The invention concerns an aircraft with wings which are fixed for flight and which may both swing and fold when the aircraft is not in flight.
Aircraft have been using wings to make manned, controlled flights for over 100 years, starting with the airplane flown by the Wright brothers in 1903. Aircraft have advantages in speed and freedom of movement, yet they are, compared with many machines of similar complexity, relatively rare. Aircraft have only been produced in numbers of a few thousand of each individual type. Aircraft use has been confined mainly to warfare and to the carrying of paying passengers in largest and fastest airplanes practical between huge airports on the outskirts of large cities. The inventor supposes the lack of production of aircraft and of flexibility in their use may be due in part to the difficulty in storing airplanes and maneuvering them when not in flight.
Airplanes lift themselves by the action of fixed wings on the air, and the greater the amount of air, the more efficient is the lifting. This fact makes a large wingspan, as compared with the weight of the aircraft, very important to high efficiency. Only with structurally efficient materials, design and construction can an airplane be equipped with efficient wings. Such wings, which are rigid and span a relatively large space, have made airplanes difficult to store. Only airplanes designed for naval warfare, and so for storage aboard ships, have commonly used wings that are customarily folded upon landing and then unfolded again for flight. The inventor supposes an aircraft with folding wings that offer sufficient benefit in comparison with their added weight and cost has been lacking.
An exemplary design for an airplane for naval warfare is that of the F-14 Tomcat, which was constructed with wings that swing, rather than fold. That is, the wings rotate approximately in their own plane, maintaining the same orientation with the ground, and rotating about an essentially vertical axis. The swinging wings are useful to reduce wing span not only for storage aboard ship, but also to greatly improve speed and maneuvering while flying at high speeds. With swinging wings, however, the solid area of the aircraft when viewed from above, that is in plan or in the top view, is essentially unchanged, the F-14 barely fit aboard the largest ships, and the F-14 cannot itself operate on the water.
Airplanes are challenging to store because they are designed to fly. One aspect of this challenge is that a parked airplane may be blown about by a strong wind, especially if the airplane is relatively light, such as an airplane for carrying a few people. Swinging wings, such as those on the F-14, do only a little to reduce this problem, since they reduce wing span but do not significantly reduce the solid area of the aircraft in plan. Known folding wings may reduce the solid area of an aircraft in plan, but if so, they typically add solid area in the side view, area which is also affected by winds on the ground or at sea. Another aspect of this challenge of storage is that the wings may be somewhat easily damaged while on the ground or at sea, and swinging alone or folding alone typically does little or nothing, besides reducing wing span, to protect the wings.